As we've all read here, past a certain level of security more money doesn't make you happier. You have more than enough money and savings for what passes as security in the US. My guess is that you're sad or depressed about one thing, but looking at the rich issue instead of whatever it is that's troubling you.

Fundamentally, as you can see from other comments, you don't seem to have an obvious reason for depression just from what you wrote, in fact you look like you have a pretty good situation. Yet you feel like you do, so there's likely something else going on.

You should make contact with a counselor or similar, and do some exploration as to what might be bothering you. Many times we don't know what's bothering us, we just feel bad. The result of counseling could be identification of some issue and how to address it, and additionally some idea of things you can do to make yourself feel good, independent of any issues.

Mental health is not just fixing what's broke. Promoting what's good is just as important.

You sound mentally unhealthy. You wouldn't hesitate to set a broken arm and put it in a cast. Go talk to a professional or two, and get yourself healthy.

EDIT: This should have been a reply to the OP. Weird that I put it here. Recalibrating brain ...